Scientists said on Thursday they had shown the human body regenerates heart cells at a rate of about one percent a year, a discovery that could one day reduce the need for transplants.
The study of 50 volunteers, using a dating method that detects traces of a carbon isotope left by Cold War nuclear bomb tests, raises the prospect of artificially stimulating the renewal process some day, they reported in the journal Science.
“Taking advantage of the heart’s own capacity to generate new cells either using pharmaceutical compounds or, if it is possible, by exercise or any other environmental factor.”
Heart cells are unusual in that they stop dividing early in life. Doctors knew there were master cells called stem cells in the heart, but heart muscle usually simply forms scar tissue after damage and never fully regenerates. …
Frisen said the rate at which the new cells are produced slows as we get older, with a young adult in their twenties renewing cells at a rate of about 1 percent a year, falling to half a percent a year by the age of 75.
“If you exchange cells at this rate it means that even if you live a very long life you will not have exchanged more than 50 percent of your cells,” said Frisen. “So at any given time your heart is a mosaic of cells you carry with you from birth and cells that that have been added later to replace cells that have been lost during life.”
The finding could also help scientists determine whether some people are predisposed to heart disease, by looking at the heart’s ability to renew cells.
If memories and emotions are stored in the heart muscle and/or the heart’s brain, if heart cells are damaged by romantic disappointment, then taking several years to heal after a heart break now makes much more sense. Even if that theory is wrong, it is great to know that hearts do heal.
Did you know your heart has a brain of its own?
The heart’s nervous system contains around 40,000 neurons, called sensory neurites, which detect circulating hormones and neurochemicals and sense heart rate and pressure information. – link
According to David Sousa, “They come in different sizes, but it takes about 30000 brain neurons to fit on the head of a pin.”